title: Pathophysiology of paradoxical embolism: evaluation of the role of interatrial septum anatomy based on the intracardiac echocardiography assessment of patients with right-to-left shunting.
abstract: BACKGROUND
  Detailed anatomic variants of the interatrial septum in patients with right-to-left shunt and contribution of specific anatomies to the risk of ischaemic recurrences has not yet been comprehensively classified.
  
  
  OBJECTIVE
  To report a classification of the anatomic variants of the interatrial septum as observed by intracardiac echocardiography and its correlation with clinical and functional characteristics.
  
  
  METHODS
  We retrospectively reviewed the medical and instrumental data of 520 consecutive patients (mean age 44±15. 5 years, 355 women) who had over a 10-year period undergone intracardiac echocardiography and right-to-left shunt catheter-based closure. The four main features used to analyse were: (a) diameter of the oval fossa, (b) presence and length of the channel, (c) presence and degree of atrial septal aneurysm, and (d) rim thickness. The presence of Eustachian valve was also tabulated.
  
  
  RESULTS
  The combinations of interatrial septum anatomical features were classified into six main anatomical subgroups. Recurrent embolism, multiple ischaemic foci on brain magnetic resonance imaging, high grade shunt, and permanent shunt before transcatheter closure procedure were associated with type 2, type 4, and type 6. Type 4 anatomical subtype (OR 4.1, 1.5-8 [95% CI], p<0.001) and type 2+presence of Eustachian valve (OR 4.3, 1.6-9 [95% CI], p<0.001) were the strongest predictors of recurrent ischaemic events before transcatheter closure.
  
  
  CONCLUSIONS
  Our study showed that interatrial septum anatomy greatly differs among patients with right-to-left shunt, as well as the risk of ischaemic recurrences in different anatomies.
authors.affiliation: 1Section of Adult Congenital and Adult Heart Disease,Cardiovascular Diagnosis and Endoluminal Interventions,Rovigo General Hospital,Rovigo,Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Rigatelli
authors.affiliation: 1Section of Adult Congenital and Adult Heart Disease,Cardiovascular Diagnosis and Endoluminal Interventions,Rovigo General Hospital,Rovigo,Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Dell'Avvocata
authors.affiliation: 2Interventional Cardiology,National Heart Institute,Sofia,Bulgaria.
authors.forename: Dobrin
authors.initials: D
authors.lastname: Vassiliev
authors.affiliation: 3Brody School of Medicine at East Carolina University,United States of America.
authors.forename: Ramesh
authors.initials: R
authors.lastname: Daggubati
authors.affiliation: 3Brody School of Medicine at East Carolina University,United States of America.
authors.forename: Ashesh
authors.initials: A
authors.lastname: Buch
authors.affiliation: 4CAMC Vascular Center of Excellence,West Virginia University,Charleston,West Virginia,United States of America.
authors.forename: Aravinda
authors.initials: A
authors.lastname: Nanjiundappa
authors.affiliation: 1Section of Adult Congenital and Adult Heart Disease,Cardiovascular Diagnosis and Endoluminal Interventions,Rovigo General Hospital,Rovigo,Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Giordan
authors.affiliation: 1Section of Adult Congenital and Adult Heart Disease,Cardiovascular Diagnosis and Endoluminal Interventions,Rovigo General Hospital,Rovigo,Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Oliva
authors.affiliation: 1Section of Adult Congenital and Adult Heart Disease,Cardiovascular Diagnosis and Endoluminal Interventions,Rovigo General Hospital,Rovigo,Italy.
authors.forename: Dario
authors.initials: D
authors.lastname: Adami
authors.affiliation: 1Section of Adult Congenital and Adult Heart Disease,Cardiovascular Diagnosis and Endoluminal Interventions,Rovigo General Hospital,Rovigo,Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Cardaioli
mesh_terms: D000328:Adult; D054087:Atrial Septum / Q000000981:diagnostic imaging*; D006328:Cardiac Catheterization; D004452:Echocardiography / Q000379:methods*; D019320:Embolism, Paradoxical / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D019160:Endosonography / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006325:Heart Atria / Q000000981:diagnostic imaging; D006344:Heart Septal Defects, Atrial / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008297:Male; D012189:Retrospective Studies; D013997:Time Factors